(ql:quickload :cl-ppcre)

(setf *stack* '((W P G Z V S B) (F Z C B V J)
		(C D Z N H M L V) (B J F P Z M D L)
		(H Q B J G C F V) (B L S T Q F G) (V Z C G L)
		(G L N) (C H F J)))

(defun replace-stack (list pos)
  (setf (nth pos *stack*) list))

(defun move-one (src dest)
  (progn
    (replace-stack (cons (car (nth src *stack*)) (nth dest *stack*)) dest)
    (replace-stack (cdr (nth src *stack*)) src)))

(defun move-two (count src dest)
  (progn
    (replace-stack (append (subseq (nth src *stack*) 0 count) (nth dest *stack*)) dest)
    (replace-stack (subseq (nth src *stack*) count (length (nth src *stack*))) src)))

(defun part-one (input)
  (progn
    (loop :for line :in (uiop:read-file-lines input) :do
      (ppcre:register-groups-bind (count src dest) ("(\\d+).*(\\d+).*(\\d+)" line)
	(dotimes (i (parse-integer count))
	  (move-one (- (parse-integer src) 1) (- (parse-integer dest) 1))))))
  (mapcar #'first *stack*))

(defun part-two (input)
  (progn
    (loop :for line :in (uiop:read-file-lines input) :do
      (ppcre:register-groups-bind (count src dest) ("(\\d+).*(\\d+).*(\\d+)" line)
	(move-two (parse-integer count) (- (parse-integer src) 1) (- (parse-integer dest) 1)))))
  (mapcar #'first *stack*))